Shift Work and Early Arterial Stiffness: A Systematic Review.

Shift work is a way of organizing rotating schedules throughout the day. This can include 1-3 shifts for the same person on a rotational basis with other workers. Schedules that include night work have been associated with cardiovascular risk, mainly due to circadian misalignment. This systematic review sought to determine whether shift work is a risk factor for increased arterial stiffness. A systematic review of different databases was performed, using the following keywords: work shift, night work, arteriosclerosis, vascular stiffness, arterial stiffness, pulse wave velocity, and their Medical Subject Headings. We selected and analyzed 11 articles regarding pulse wave velocity as an indicator of arterial stiffness. Two studies identified higher levels of arterial stiffness in shift workers compared to day workers, while two studies found the opposite. In addition, four studies found no differences in arterial stiffness between shifts, two studies associated shorter sleep duration with arterial stiffness, and one study observed that physical activity could prevent adverse cardiovascular outcomes in shift workers. The findings are heterogeneous and preclude any robust conclusions. However, the present review points to the need for further studies to investigate arterial stiffness in shift workers, with greater control for confounding factors and longitudinal design.

Acute effects of time-restricted feeding in low-income women with obesity placed on hypoenergetic diets: Randomized trial.

OBJECTIVE: The aim of this study was to evaluate the acute effects of time-restricted feeding in obese women living in social vulnerability who were placed on diets with the same energy deficit. METHODS: Fifty-eight obese women (19-44 y of age) were randomized to a group with a hypoenergetic diet and 12 h of fasting daily or to a group with only a hypoenergetic diet for 21 d, with body weight and waist circumference monitoring up to 81 d of intervention. The determination of the individual's energy content of the diets was based on their resting metabolic rate (by indirect calorimetry) and physical activity level (by triaxial accelerometers). Body composition, temperature, blood pressure, appetite, adhesion difficulty, thyroid axis hormones, leptin, glucose concentration, and insulin were measured before and after 21 d of intervention. A mixed analysis of variance test was performed. RESULTS: The women had a mean age of 31 y and mean body mass index of 33 kg/m². Significant interaction between group × time was observed only in axillary temperature (0.44°C; 95% confidence interval [CI], 0.17-0.74°C; P < 0.01), which increased in the experimental group and in body fat (-0.75%; 95% CI, -1.43% to -0.07%; P = 0.02) decreased in the experimental group. Also, there was a significant decrease in waist circumference in the time-restricted feeding group after 81 d. There were no differences in hormonal profile, resting metabolic rate, reported appetite, or adherence difficulty. CONCLUSION: Time-restricted feeding may be considered an alternative strategy for treating obesity in socially vulnerable women.

Agreement between the total energy expenditure calculated with accelerometry data and the BMR yielded by predictive equations v. the total energy expenditure obtained with doubly labelled water in low-income women with excess weight.

Low-income women are the group with the highest levels of obesity worldwide. In low-income settings, the use of predictive equations, which yield a measure of the individuals' BMR, is a feasible approach to estimate the individuals' total energy expenditure (TEE), using the factorial method (calculated-TEE = BMR × physical activity level), an important step of the obesity nutritional care. The present study aimed to identify the predictive equation that, in conjunction with metabolic equivalents of tasks (MET) data from accelerometers, yields the calculated-TEE with better agreement compared with the TEE measured by doubly labelled water (TEE-DLW). Forty-five women aged 19-45 years, with excess weight and mothers of undernourished children, were included. They received DLW to determine TEE (14 d); at the same time, they used triaxial accelerometers (7 d) to estimate their MET. The Bland-Altman method, paired-sample t tests, concordance correlation coefficient and root-mean-square error were used to assess the agreement. Maximum allowed differences were defined as 24 %, based on the within-variance coefficient of the energy intake of the sample. Eleven equations were studied. The calculated-TEE obtained by five equations showed non-significant bias: Dietary Reference Intake (Institute of Medicine (2005) Dietary Reference Intakes for Energy, Carbohydrate, Fiber, Fat, Fatty Acids, Cholesterol, Protein, and Amino Acids), FAO/WHO/UNU ((2001) Food and Nutrition Technical Report Series), Harris & Benedict ((1919) Proc Natl Acad Sci USA4, 370-373), Henry & Rees ((1991) Eur J Clin Nutr45, 177-185) and Schofield ((1985) Hum Nutr Clin Nutr39, 5-41). The mean percentage differences were -1·5, -0·8, 2·2, -2·2 and 2·0 %, respectively. Considering all parameters, FAO/WHO/UNU ((2001) Food and Nutrition Technical Report Series) equation performed slightly better than the others; nevertheless, no equation in conjunction with the estimated-MET showed a calculated-TEE with its CI for the Bland-Altman limits of agreement inside the pre-defined acceptable range.